No errors...But display is blank

[Just Me]

Try forcing the problem monitor to use the NVidia graphics card. A quick test would be to disable the Intel graphics via display manager.

[eightman8]

(revised)

Okay. That worked in like seconds. Monitor image popped right on. Awesome.
Disabling the display adapter did cause problems.
When I restarted the laptop screen was blank. I had to plug the usb monitor in to re-enable the Intel adapter.
Which made the laptop screen work… and the usb monitor not-work.
Also, some programs didn’t work correctly.
Video playback was irregular, sometimes it was fine. Strange.

So… the only way to get the monitor to work is to…
Boot the laptop with both adapters enabled.
Then disable the Intel adapter.
Work with both monitors, but with fickle performance.
Then remember to re-enable the Intel adapter before shut down.
*Repeat process every time you want to use the monitor.

Thanks 'Just Me'. I do think you nailed the problem. It is definitely the dueling display adapters.
But until I can manually choose an adapter for each screen… it’s jury-rigged.
Or unless the intellects at DisplayLink can figure a workaround for us dual adapter losers.

[Just Me]

I was able to force my external monitors to run on the NVidia card and the laptop to run on the Intel. Unfortunately, I forgot how I did it.

I ran so many troubleshooting steps trying to fix this that I cannot say for sure. You might try installing new USB drivers from the manufacturer's website. I had to follow these steps to update my USB drivers as Intel does not write any for Windows 8:

http://plugable.com/2012/12/01/windo...st-controllers

I also disabled the following Intel services - hkcmd Module, igfxTray Module, and persistence Module. They were set to auto start but are now set to disabled.

You can download DevManView from nirsoft.net and write a batch file to run at startup to automatically enable the Intel graphics card. At least then if you forget to re-enable it before shutdown, you will be able to use your laptop when you are away from your external monitors.

[Just Me]

To use DevManView automatically you will have to turn off UAC. There is a way to turn it off for one application only. Microsoft released a KB on how to do it and then withdrew it. This page goes over the details:

http://www.wintuts.com/Disable-UAC-f...n-applications

I have not tried it. There is also an application that turns off UAC for selected applications called UAC Trust Shortcut. I have not used it either.